Dreams may hold hidden health secrets

By Todd Neale | Fact-checked by Barbara Bekiesz

Published June 27, 2024

Key Takeaways

Prodromal dreaming, the idea that dreams can contain indicators of real medical issues, is a controversial topic in the medical community.
There is, however, some evidence that vivid dreams, particularly nightmares, may signal current or future health problems.
When your patients report abnormal dreams or nightmares, it may be worth exploring potential mental or physical health issues.

Dream interpretation remains a highly subjective exercise, although psychiatrists and therapists may use a patient's dreams to help tackle their concerns.

But what if there is more to be found within our dream states, including hints of medical issues like Parkinson’s disease and cancer that have not yet been diagnosed or may potentially develop at some point in the future?

Prodromal dreaming

The concept, called prodromal dreaming, “is controversial in broader medical professions,” psychologist Deirdre Leigh Barrett, PhD, a past president of the International Association for the Study of Dreams, told Discover.^[]

Yet the concept persists because of anecdotal reports. In one of Dr. Barrett’s books, she describes an individual who had a dream that was pivotal in getting them a diagnosis for a potentially life-threatening health issue.

A man dreamt that he had been bitten on the back by a panther. When he woke up, he saw a mark on his back at that spot. The dream compelled him to see a doctor to check it out, and he was ultimately diagnosed with cancer.

Some research has been emerging over the past several years to provide more definitive evidence that dreams, in some cases, might be signaling serious health issues that require medical attention.

Portending mental and physical health issues

According to Michelle Drerup, PsyD, DBSM, a behavioral sleep medicine expert at the Cleveland Clinic, “there’s no real consistent, scientifically proven theory linking specific content back to what a dream means.”^[]

It is thought, however, that dreaming helps people sort through their emotions, with nightmares and stressful dreams more likely in those who are particularly anxious or depressed during waking hours. Nightmares also could be an aspect of post-traumatic stress disorder (PTSD), representing a way of experiencing the original trauma all over again.

But it is not just mental health that may be playing into our dream state. People dreaming about their teeth falling out, for instance, may be grinding their teeth during sleep, a condition called bruxism. Or discontinuing antidepressant therapy—which suppresses rapid eye movement (REM) sleep, when the most vivid dreams occur—may cause a “REM rebound” and a change in dreaming, according to Dr. Drerup.

A similar phenomenon also may occur with treatment for sleep apnea, which is associated with fragmented sleep. A review in Frontiers in Neurology, though, shows conflicting results of studies delving into the link between sleep apnea and dream recall or content.^[]

Dreams as a prelude to more serious conditions

What happens during the dream state may portend bigger medical problems in the future, too.

REM sleep behavior disorder is characterized by a lack of the typical temporary paralysis that occurs during REM sleep, allowing affected people to move around, with clear safety concerns. It is also associated with abnormal dreaming.

Several studies have demonstrated that up to about 80% of people with the disorder will eventually develop Parkinson’s disease or other similar neurodegenerative diseases years later, according to a review in Parkinsonism & Related Disorders.^[]

There is some evidence, too, that nightmares are an indicator of heart disease. In a study in Sleep, for example, military veterans who reported having nightmares that were severe, frequent, or both, had greater odds of having signs of high blood pressure or heart problems, even after adjusting for PTSD diagnosis.^[] And an earlier study demonstrated an increase in perceived spasmodic chest pain and irregular heartbeat in women ages 50 to 64 who reported frequent nightmares and poor sleep.^[]

A 2024 study published in eClinicalMedicine explored the timing on onset for neuropsychiatric symptoms in patients with systemic lupus erythematosus (SLE) and other systemic autoimmune rheumatic diseases (SARDs).^[]

The researchers found that many such symptoms may arise before any clinical diagnosis. Among the patients who had hallucinations, many (61% with SLE and 34% with other SARDs) reported “increasingly disrupted dreaming sleep (usually nightmares)” before the hallucinations started.

And when it comes to dreams and cancer, there is at least some evidence bolstering anecdotes, such as the one involving a bite from a panther. In a small study published in Explore, researchers surveyed 18 women with breast cancer who reported having “warning dreams” before their diagnosis.^[] Not only did most of the women say that “the dreams were more vivid, real, or intense than ordinary” (83%) and involved “an emotional sense of threat, menace, or dread” (72%), but many also said the dream included use of the words “breast cancer/tumor” (44%) or a sense of physical contact with their breast (39%).

“Warning dreams of breast cancer were often reported to be life changing experiences that prompted medical attention leading directly to diagnosis,” the authors concluded.

What this means for you

Though the concept that dreams contain clues about our mental and physical health status is controversial, there is some evidence linking what happens in dreams to medical conditions like Parkinson’s disease, heart disease, and systemic autoimmune rheumatic diseases, and even cancer.